A numerical controller capable of precisely controlling a machine tool having an axis (C-AXIS) for turning a table with a simple machining program and easily coping with variation of a tool length. A machining path is commanded in a workpiece coordinate system (ΣW) turning with a table. The commanded machining path for linear-motion axes (X, Y, Z) is interpolated based on a commanded machining velocity, to obtain interpolated positions on the machining path. Also the commanded motions for rotational-motion axes (A-AXIS, C-AXIS) are interpolated to obtain interpolated positions for the rotational-motion axes. The interpolated position for the linear-motion axes is corrected based on the interpolated position of the rotational-axes. The servomotors for the linear-motion axes are driven based on the corrected interpolated positions and the servomotors for the rotational-motion axes are based on the interpolated positions of the rotational-motion axes. Since the workpiece coordinate system turns with the table, a machining shape defined in the workpiece coordinate system is realised on the workpiece turning with table.